terrifying images from the sky. This evening, investigators are trying to figure out what caused a hot air balloon with nearly two dozen people inside in one of the biggest tourist destinations in the world, to explode and plummet to the ground. Here are the images of it, as it was falling from the sky, the last few seconds before it crashed. Tonight, the death toll at 19, and abc's alex marquardt leads us off from egypt. Reporter: This amateur video shows the moment the vacation of a lifetime turned into tragedy. A sunrise balloon ride suddenly enveloped in black smoke. You can see it billowing from the basket. Then the balloon begins to collapse. Deflated, it now plummets a thousand feet down to earth. Photographer christopher michel watched it all unfold from another balloon. We heard a loud explosion and then a lot of smoke right behind us. Our first feeling was it couldn't be a balloon but it turned out actually to be, unfortunately, this tragic accident. Reporter: We now know that at 7:00 a.M. The balloon was coming in for a landing in a sugar cane field. That's when one of its cables got caught on a helium canister and started a fire. A pilot and two others jumped from 40 feet up as the balloon then shot back into the sky, exploding into flames before crashing down. 19 lives were lost, including one of those who jumped. They were from hong kong, japan and across europe. It's a marvel to float in a balloon over luxor, flying over the desert with its remains of ancient egypt, the temples, the tomb of the pharaohs. Those are some of the greatest sights for tourists to see in this country. And this accident couldn't have come at a worst time. Egypt's tourism industry has been decimated since the revolution two years ago. The government is now investigating how this tragedy could have happened. David? Alex maher quart leading us off tonight from cairo. Alex, thank you. And we have reported here on balloon accidents back here in In fact, last year alone, 15 of them. This one, just last month in san diego, the view from inside the basket as this balloon crash lands. Tonight, abc's cecilia vega with an air balloon pilot who investigated hundreds of crashes. She watched the video with him today. Reporter: Have you ever seen anything like this? No, no. Happens pretty fast and they're going to hit really hard. Jumping off a ten-story building. Looking at how much smoke you had and how fast, it looked like it was an intense fire. I would guess the major injuries are occurring there beforehey get to the ground. Reporter: They have any chance? Looking at the flames, i don't think so. Reporter: From looking at this, do you have any sense of what caused this? If I were investigating this, that's the first thing I look at, the aircraft. To see if I can see fuel lines that are clearly not hooked up to the tanks, so you know that would be the culprit. Reporter: These balloons are so magnificent, you have the beautiful sceneries underneath. This can be dangerous. Yeah, it could be. But from an accident safety standpoint, balloons are about ten times safer than airline travel.

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